1. Field of the Invention
The present invention relates to analog electrical circuits. In particular, the present invention is a circuit for summation of analog voltages.
2. Description of the Prior Art
A common function to be performed in analog electrical systems is voltage summation. Various circuits have been developed in the past to provide this function. The most common type of circuitry uses an operational amplifier. For example, one typical type of voltage summation circuit includes an operational amplifier having a capacitor connected between its output terminal and its non-inverting input terminal. The input voltage is supplied through a resistor to the non-inverting input of the operational amplifier, and the inverting input of the operational amplifier is connected to ground. The output voltage appearing at the output of the operational amplifier represents a summation of the input voltage signals supplied to the circuit. In the design of integrated circuits, it is advantageous to minimize the number of components, and thus the size of the integrated circuit. A voltage summation circuit having a smaller component count than an operational amplifier circuit would be particularly advantageous for analog integrated circuits requiring a voltage summation function.